Design and Simulation of All-Optical Plasmonic Logic Gates Based on Nano-Ring Insulator-Metal-Insulator Waveguides

Abstract

       In this article, all-optical logic gates were proposed based on plasmonic insulator-metal-metal (IMI) waveguide. (IMI) the waveguide has an important feature which is confining the applied light far beyond its diffraction limit. Thus, the designed structure will result in ultra-compact and minimum size. The proposed gates are OR, AND, NOT, NOR, NAND, EX-OR, and EX-NOR. The behaviors of the proposed gates are actualized based on the optical interference property between the propagated signals through the input and the activation (control) ports. The proposed gates are simulated and realized using a single structure with dimensions of (350 ´ 350 nm), the operation wavelength was (1550 nm). The performance of the designed plasmonic gates is tested by measuring two parameters; the normalized optical transmission, and the contrast ratio which is the ratio between the transmissions of (ON) state to the transmission of (OFF) state. The proposed structure realizes all the basic logic gates in the same structure with ultra-compact design and a good contrast ratio.